1. Field of the Invention
The present invention relates to a plasma discharge apparatus, and more particularly to a method and an apparatus having pin electrode for surface treatment using capillary discharge plasma shower. Although the present invention is suitable for a wide scope of applications, it is particularly suitable for plasma treatment of workpieces under an atmospheric pressure or a high pressure, thereby providing virtually unrestricted applications regardless of size of the workpieces.
2. Discussion of the Related Art
A plasma discharge has been widely used for treating surfaces of a variety of workpieces in many different industries. Particularly, a station for cleaning or etching electronic components, such as a printed circuit board (PCB), lead frame, microelectronic device, and wafer, has been employed in electronics industries since it provides advantages over the conventional chemical cleaning apparatus. For example, the plasma process occurs in a closed system instead of in an open chemical bath. Thus, the plasma process may be less hazardous and less toxic than the conventional chemical process. One example of a related background art plasma process and apparatus was disclosed in U.S. Pat. No. 5,766,404.
Another example of the related background art was disclosed in xe2x80x9cSurface Modification of Polytetrafluoroethylene by Ar+Irradiation for Improved Adhesion to Other Materialsxe2x80x9d, Journal of Applied Polymer Science, pages 1913 to 1921 in 1987, in which the plasma process was applied on the surfaces of plastic workpieces in an effort to improve wetability or bonding of the workpieces.
All of the background art plasma processes, however, have to be carried inside a treatment chamber because the background art plasma processes can only be performed under a vacuum condition. Thus, when a workpiece is too big to be treated in the chamber, the background art plasma process cannot be used to treat the workpiece. As a result, the background art plasma processes are very limited in applications.
Accordingly, the present invention is directed to a method and an apparatus for plasma treatment using capillary discharge plasma that substantially obviate one or more of the problems due to limitations and disadvantages of the related art.
Another object of the present invention is to provide a method and an apparatus for plasma treatment using capillary discharge plasma which can be applied in sterilization, cleaning, etching, surface modification, or deposition of thin film under a high pressure or an atmospheric pressure condition.
Additional objects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.
To achieve the objects and in accordance with the purpose of the invention, as embodied and broadly described herein, an apparatus for treating a workpiece using a plasma includes at least one pin electrode for receiving a power source, a dielectric body having first and second sides, wherein the first side is coupled to the pin electrode and the second side has at least one capillary extending to a direction of the first side of the dielectric, and each capillary is substantially aligned with each pin electrode, and a counter electrode electrically coupled to the pin electrode for generating the plasma from each capillary.
In another aspect of the present invention, an apparatus for treating a workpiece using a plasma includes a dielectric body having at least one opening extending therethrough, at least one dielectric tube having first and second openings, wherein the dielectric tube coupled to the dielectric body through the opening of the dielectric body, at least one pin electrode coupled to the first opening of the dielectric tube, and a counter electrode electrically coupled to the pin electrode for generating the plasma.
In another aspect of the invention, a method of treating a workpiece using a plasma discharge apparatus includes the steps of placing the workpiece in close proximity to the apparatus, wherein the apparatus includes, at least one pin electrode for receiving a power source, a dielectric body having first and second sides, wherein the first side is coupled to the pin electrode and the second side has at least one capillary extending to a direction of the first side of the dielectric, and each capillary is substantially aligned with each pin electrode, and a counter electrode electrically coupled to the pin electrode, applying a potential to the pin electrode and the counter electrode, and generating a plasma out of the capillaries.
In a further aspect of the present invention, a method of treating a workpiece using a plasma discharge apparatus includes the steps of placing the workpiece in close proximity to the apparatus, wherein the apparatus includes, a dielectric body having at least one opening extending therethrough, at least one dielectric tube having first and second openings, wherein the dielectric tube coupled to the dielectric body through the opening of the dielectric body, at least one pin electrode coupled to the first opening of the dielectric tube, and a counter electrode electrically coupled to the pin electrode, applying a potential to the pin electrode and the counter electrode, and generating a plasma out of the capillaries.
Furthermore, several workpieces can be automatically treated by the apparatus by placing the workpieces on a conveyer that passes under the plasma.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are needed to provide further explanation of the invention as claimed.